very variable in size and shape, usually a half cup-shaped or semi-circular scale on the lower side of the sorus, sometimes small and indistinct, often deciduous. Sporangia numerous, sessile or nearly so, bursting transversely; ring somewhat oblique, complete.
A tropical or subtropical genus, containing about 45 species, 30 of which are natives of America, the remainder scattered through the warm regions of the Old World. It only differs from Cyathea in the small one-sided involucre, and several species might be referred to either genus. The single species found in New Zealand is endemic.
1. H. Smithii, Hook. ex Hook, and Baker Syn. Fil. 31.—Trunk 6–25 ft. high, about 9 in. diam., coated with fibrous aerial rootlets below, clothed towards the top with the pendulous withered rhachides of the old fronds. Fronds numerous, horizontally spreading, 5–9 ft. long, bipinnate, lanceolate or oblong-lanceolate, acute but hardly acuminate, thin and membranous, bright fresh-green. Stipes slender, clothed at the base with a dense brush of long shining chestnut-brown subulate-lanceolate scales, slightly asperous beneath; rhachis pale yellow-green, almost glabrous when old, when young clothed with strigillose hairs above, and with lax deciduous scales beneath. Primary pinnæ 9–15 in. long, 3–4 in. broad, linear-oblong, acuminate; costæ clothed with strigillose hairs above, paleaceous or glabrous beneath; secondary pinnæ 1½–2½ in. long, pinnatifid above, pinnate at the base. Segments linear-oblong, acute, slightly falcate, coarsely serrate. Sori copious, on the fork of the veins. Indusium hemispherical, on the costal side of the sorus, variable in size, sometimes almost wrapping round the sorus at the base.—Thoms. N.Z. Ferns, 29; Field, N.Z. Ferns, 46, t. 9, f. 5. Cyathea Smithii, Hook. f. Fl. Nov. Zel. ii. 8, t. 72; Handb. N.Z. Fil. 350. C. stellulata, Col. in Trans. N.Z. Inst. xviii. (1886) 222.
Var. microphylla, Cheesem.—Fronds fewer in number, soft, delicately membranous, pale grass-green; rhachis densely strigillose above, paleaceous beneath. Primary pinnæ rather narrower and more acuminate. Segments smaller, entire or bluntly crenulate towards the tip.—H. microphylla, Col. in Trans. N.Z. Inst. xxvii. (1895) 399.
North and South Islands, Stewart Island: Abundant in damp hilly forests from Kaitaia (Mongonui County) southwards. Sea-level to 2000 ft. Auckland Islands: Norman Inlet, rare, W. Joss ex Cockayne!
A very beautiful species, with the most tender fronds of any New Zealand tree-fern. The trunk is not uncommonly forked or branched above; and Mr. Buchanan (Trans. N.Z. Inst. xix., 217) describes and figures a remarkable specimen which had no less than 16 well-developed branches. H. Smithii and Dicksonia squarrosa are plentiful through the whole of the lowland districts of Stewart Island, in S. lat. 47° 20′, and the former species has recently been found in the Auckland Islands (S. lat. 50° 40′), the extreme southern limit of arborescent ferns.
